OBTAINING METHOD AND DEVICE FOR CHANNEL INFORMATION

• US 20130136065A1
• Filed: 10/19/2010
• Published: 05/30/2013
• Est. Priority Date: 04/30/2010
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Chen, Yijian, Xu, Jun, Li, Yu Ngok, Zhang, Junfeng
• Granted Patent: US 8,830,932 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0417 Feedback systems
• CPC Class Codes: H04B 7/0469 taking special antenna structures, e.g. cross polarized antennas into account
• CPC Class Codes: H04B 7/0486 taking channel rank into account
• CPC Class Codes: H04B 7/0626 Channel coefficients, e.g. channel state information [CSI]
• CPC Class Codes: H04B 7/063 Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection
• CPC Class Codes: H04B 7/0639 Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection
• CPC Class Codes: H04B 7/0645 Variable feedback
• CPC Class Codes: H04L 1/0031 Multiple signaling transmission H04L1/1664, F15 take precedence
• CPC Class Codes: H04L 2025/03808 Transmission of equaliser coefficients
• CPC Class Codes: H04L 25/03923 according to the rank
• CPC Class Codes: H04L 25/03949 equalizer selection or adaptation based on feedback multiple signaling inclusive of a precoding command for adapting the transmitter H04L1/0031; feedback for transmit diversity systems H04B7/0619; selection of codebook or precoding matrix for MIMO diversity systems H04B7/0456
• CPC Class Codes: H04W 72/563 of the wireless resources

Abstract

A method and device for acquiring channel information are disclosed in the present invention, to solve a technical problem in the related art that the channel information cannot be fed back flexibly according to requirements. The method includes: for one subband, User Equipment (UE) acquires Rank Indicator (RI) information of a current channel, in which the RI information indicates a rank (ν) of the current channel, and ν is a positive integral number not greater than 8; the user equipment determines the quantity of the Precoding Matrix Indicator (PMI) information required to be fed back to a base station according to ν, and transmits the PMI information in said quantity and the RI information to the base station; the base station acquires the channel information of said subband according to the PMI information in said quantity and said RI information.

Claims

1. A method for acquiring channel information, comprising:

for one subband, a User Equipment (UE) acquiring Rank Indicator (RI) information of a current channel, wherein a rank (ν

) of said current channel is indicated in the RI information, and ν

is a positive integral number not greater than 8;

the user equipment determining the quantity of Precoding Matrix Indicator (PMI) information required to be fed back to a base station according to ν

, and transmitting the PMI information in said quantity and the RI information to the base station; and

the base station acquiring channel information of said subband according to the PMI information in said quantity and said RI information.

2. The method according to claim 1, wherein the step of the user equipment determining the quantity of Precoding Matrix Indicator (PMI) information required to be fed back to a base station according to ν

comprises;

when ν

is greater than or equal to N0, the user equipment determining that the quantity of the PMI information required to be fed back to the base station is m; and

when ν

is less than N0, the user equipment determining that the quantity of PMI information required to be fed back to the base station is m+1;

wherein N0 is an integral number greater than 0 and less than or equal to 8, and m is an integral number determined according to a level of feedback precision of the user equipment.

3. The method according to claim 2, wherein the step of the user equipment determining the quantity of PMI information required to be fed back to a base station according to ν

further comprises;

when ν

is less than N1, the user equipment determining that the quantity of the PMI information required to be fed back to the base station is m+2;

wherein N1 is an integral number less than N0 and greater than 0.

4. The method according to claim 1, wherein

the PMI information in said quantity comprises at least first Precoding Matrix Indicator (PMI1) information.

5. The method according to claim 4, wherein the step of the base station acquiring the channel information of said subband according to the PMI information in said quantity and said RI information comprises:

when the quantity of said PMI information is 1, the base station seeking out a code word W1 from a first codebook according to said PMI1 information and RI information, and acquiring the channel information of said subband according to the code word W1 and a function F (W1, W2, . . . , Wn) of n−

1 matrixes, or the base station representing the code word W1 as the channel information of said subband, wherein said n−

1 matrixes are convention values, and n is an integral number;

or the base station directly acquiring the channel information of said subband according to the code word W1; and

when the quantity of said PMI information is r, the base station seeking out the code word W1 from the first codebook according to said PMI1 information and RI information, and seeking out r−

1 matrixes corresponding to other r−

1 PMI information from codebooks corresponding to said other r−

1 PMI information except the PMI1 information, acquiring the channel information of said subband according to said code word W1 and the function F(W1, W2, . . . , Wn) of said n−

1 matrixes comprising said r−

1 matrixes, wherein other n−

r matrixes except said r−

1 matrixes in said n−

1 matrixes are convention values;

or the base station acquiring the channel information of said subband according to the code word W1 and a function f(W1, W2, . . . , Wr) of said r−

1 matrixes, wherein r is an integral number greater than or equal to 2.

6. The method according to claim 5, wherein

said convention values are fixed vectors or matrixes, or are different convention values according to the Rank (ν

) of said current channel;

wherein ν

represents the rank of channel represented by said RI information.

7. The method according to claim 5, wherein

when r is equal to 2, a function F(W1, W2) comprises W1×

W2 or W2W1; and

when r is equal to 3, a function F(W1, W2, W3) comprises (W3′

*W3)×

W1×

W2 or W2(W3′

×

W3×

W1), wherein W3′

denotes a conjugate transpose matrix of W3.

8. (canceled)

9. (canceled)

10. (canceled)

11. A device for acquiring channel information, comprising:

a receiving module, which is configured to receive Precoding Matrix Indicator (PMI) information transmitted by a user equipment and Rank Indicator (RI) information of a current channel; and

an acquiring module, which is configured to acquire channel information of a subband according to said PMI information and RI information received by said receiving module;

wherein the quantity of said PMI information is determined by the user equipment according to a rank ν

of the current channel, and ν

is indicated in said RI information and ν

is a positive integral number not greater than 8.

12. The device according to claim 11, wherein

said PMI information comprises at least first Precoding Matrix Indicator (PMI1) information;

said acquiring module is configured to acquire the channel information of the subband by a following method;

when the quantity of said PMI information is 1, seeking out a code word W1 from a first codebook according to said PMI1 information and RI information; and

acquiring the channel information of said subband according to the code word W1 and a function F(W1, W2, . . . , Wn) of n−

1 matrixes, or representing the code word W1 as the channel information of said subband;

wherein said n−

1 matrixes are convention values, and n is an integral number;

or acquiring the channel information of said subband according to the code word W1.

13. The device according to claim 11, wherein

said PMI information comprises at least first Precoding Matrix Indicator (PMI1) information;

said acquiring module is configured to acquire the channel information of the subband by a following method;

when the quantity of said PMI information is r, seeking out a code word W1 from a first codebook according to said PMI1 information and RI information, and seeking out r−

1 matrixes corresponding to other r−

1 PMI information from codebooks corresponding to said other r−

1 PMI information except the PMI1 information; and

acquiring the channel information of said subband according to the code word W1 and a function F(W1, W2, . . . , Wn) of n−

1 matrixes comprising said r−

1 matrixes, wherein other n−

r matrixes except said r−

1 matrixes in said n−

1 matrixes are convention values;

or acquiring the channel information of said subband according to the code word W1 and a function f(W1, W2, . . . , Wr) of said r−

1 matrixes, wherein r is an integral number greater than or equal to 2.

14. (canceled)

15. (canceled)

16. (canceled)